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      <td class="subheader-left"><a href="matlab:open idecimate">View code for idecimate</a></td>
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<h1>idecimate</h1><p><span class="helptopic">an image</span></p><p>
<strong>s</strong> = <span style="color:red">idecimate</span>(<strong>im</strong>, <strong>m</strong>) is a decimated version of the image <strong>im</strong> whose
size is reduced by <strong>m</strong> (an integer) in both dimensions.  The image is smoothed
with a Gaussian kernel with standard deviation <strong>m</strong>/2 then subsampled.

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<p>
<strong>s</strong> = <span style="color:red">idecimate</span>(<strong>im</strong>, <strong>m</strong>, <strong>sd</strong>) as above but the standard deviation of the
smoothing kernel is set to <strong>sd</strong>.

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<p>
<strong>s</strong> = <span style="color:red">idecimate</span>(<strong>im</strong>, <strong>m</strong>, []) as above but no smoothing is applied prior
to decimation.

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<h2>Notes</h2>
<ul>
  <li>If the image has multiple planes, each plane is decimated.</li>
  <li>Smoothing is used to eliminate aliasing artifacts and the standard
deviation should be chosen as a function of the maximum spatial frequency
in the image.</li>
</ul>
<h2>See also</h2>
<p>
<a href="matlab:doc iscale">iscale</a>, <a href="matlab:doc ismooth">ismooth</a>, <a href="matlab:doc ireplicate">ireplicate</a></p>
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